/*

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements.  See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership.  The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.bff.gaia.unified.sdk.fn.data;



import java.util.concurrent.CompletableFuture;



/** An {@link InboundDataClient} backed by a {@link CompletableFuture}. */

public class CompletableFutureInboundDataClient implements InboundDataClient {

  private static final Object COMPLETED = new Object();

  /**

   * Create a new {@link CompletableFutureInboundDataClient} using a new {@link CompletableFuture}.

   */

  public static InboundDataClient create() {

    return forBackingFuture(new CompletableFuture<>());

  }



  /**

   * Create a new {@link CompletableFutureInboundDataClient} wrapping the provided {@link

   * CompletableFuture}.

   */

  static InboundDataClient forBackingFuture(CompletableFuture<Object> future) {

    return new CompletableFutureInboundDataClient(future);

  }



  private final CompletableFuture<Object> future;



  private CompletableFutureInboundDataClient(CompletableFuture<Object> future) {

    this.future = future;

  }



  @Override

  public void awaitCompletion() throws Exception {

    future.get();

  }



  @Override

  public boolean isDone() {

    return future.isDone();

  }



  @Override

  public void cancel() {

    future.cancel(true);

  }



  @Override

  public void complete() {

    future.complete(COMPLETED);

  }



  @Override

  public void fail(Throwable t) {

    // Use obtrudeException instead of CompleteExceptionally, forcing any future calls to .get()

    // to raise the execption, even if the future is already compelted.

    future.obtrudeException(t);

  }

}